The push-button automation of the Precision Pump is just one thing you'll love about this enhancement system. Designed in classic pump style, the firm, transparent cylinder is graduated in universal measurements so you can watch your progress, and the entry is lined with a removable soft jelly sleeve for comfort and to ensure an airtight seal. The pistol grip control has an easy push button that starts up the suction, meaning that there's no effort at all on your part, it's easy to grip has a quick auto-release button that sets you free in an instant. Some men swear by penis pumps as a way to gradually increase size, while prepping for unforgettable sex, find out for yourself with possibly the easiest pump available. Takes 4 AAA batteries, which are included. Total length of the cylinder is 8 1/2 inches.